Yesterday and today, "Hagar the Horrible" and "Blondie" respectively told the exact same joke. As if the cartoonists were reading from the same script:
1. Lounging, too-lazy-to-get-off-his-keister hubby inquires about dinner.
2. The missus employs a "persuasive" bid for eating out.
3. The outmaneuvered manchild utters the Exact Same Punchline.
4. Voila! A formula for high hilarity as old as Hagar's horns.

What gives? you ask. Well, speaking from experience, there are a few likely reasons. To wit:

Cartoonists are scamps. Syndicated scribblers do much of their work in isolation. How to spice up the cartooning life? "Collaborate" on an identical gag and perhaps give keen-eyed readers an added chortle.

A Son-of-Cartoonists Pact. Dean Young's dad created "Blondie"; Chris Browne's dad created "Hagar." Talk about your small clubs. The spawn of famous fathers Chic and Dik perhaps collaborated to entertain themselves -- unless they are carrying out some second-generation ritual that must never die out.

A gag writer scored the amazing double-sale of the decade. We do not know whether Young or Browne ever buy from outside writers. We just like to imagine the face of a gleeful gag writer who could pull this coup off.

Young&Browne just wanted to kindly provide Friday fodder for hungry comics bloggers. If this is the real reason, guys, then you succeeded. And we thank you. Check's in the mail.

The real reason, methinks: "Blondie" and "Hagar" have a history of crossover projects and this is just the latest one. Congrats, guys -- you keep us on our toes.

If it was supposed to be a collaboration why does the joke vary slightly?

To keep it from being too obviously the same? Doubtful. Anyone who would be thrown off by the slight change in the setup wouldn't be smart enough to connect the two to begin with.

Methinks they're probably mining the same gag writer or looking over their archives and updating. There was a Blondie used in June I think that was the exact same joke they used in the 50s. Newspapers are suckers. These two strips are perfect illustrations of it.

I typically read the daily comics several days in advance. The moment I spotted this gag duplication, I considered it my humble duty to draw readers' attention to it.

Gag life-cycles vary by cartoonist. "Pearls Before Swine's" Stephan Pastis tells us he has worked more than a half-year in advance. By comparison, syndicates accommodate some topical strip cartoonists, whose window can shrink to roughly a week-and-a-half -- from cartoonist filing date to the reader's driveway or desktop.

Generally speaking, though: Most syndicated cartoonists work at least several weeks in advance of publication date for their daily strips, and at least a month in advance for their Sunday strips.

A last note about tight deadlines: As you might imagine, cartoonists have welcomed, embraced and -- yes, routinely abused -- the awesome era of e-mail transmission. (Myself included.)

Your writer is right -- dropping For Better or For Worse is WORSE, Far Worse. For many of us the old Peanuts are very enjoyable, and that probably would apply to FBOFW.

Re: Dagwood and Hagar, I've often thought there was some idea given to cartoonists (maybe via the internet) to challenge them. Often the same idea is repeated in various cartoons on a given day or within a week but each has its own individual (and usually different) "take" on it. It's interesting. (And FYI, similarly, some denominations give ministers ideas for Sunday services.)